random exe generation problems

This is a log file for my brothers comp. Norton Firewall pops up intermittently with exes with names like dfjkdfjdkf.exe and so on. I ended processes on roughriders.exe and skinkers.exe, so not sure if HJT will show them, but they are on there. Can you let me know if that is whats causing the problem or if its something more?

Have Hijack This fix all of the following by placing a check in the appropriate boxes and hitting fix checked. Make sure all browser and all Windows Explorer windows are closed before fixing.R3 - URLSearchHook: MrSmiley Popup Blocker - {12F02779-6D88-4958-8AD3-83C12D86ADC7} - C:\Program Files\MrSmiley Popup Blocker\toolbar.dll (file missing)